Hejin, a county-level city under the jurisdiction of Shanxi Province, administered by Yuncheng City, is located in the southwestern part of Shanxi Province, in the northwestern corner of Yuncheng City, in the triangle where the Fen River and the Yellow River converge, between longitude 110°32′15″-110°50′45″E and latitude 35°28′17″-35°47′15″N, with a total area of 593 square kilometers. It has a warm-temperate continental Loess Plateau climate, with four distinct seasons due to the influence of the monsoon winds and the desert climate of Inner Mongolia. As of February 2023, Hejin has 4 streets, 3 towns, and 2 townships under its jurisdiction, with the municipal government stationed in the city streets. As of the end of 2022, Hejin had a resident population of 393,158.
In the second year of Xuanhe of the Northern Song Dynasty (1120), Longmen County was changed to Hejin County, named after the Yellow River crossing in its territory.On January 12, 1994, approved by the State Council, the city of Hejin was set up (county-level city).In October 2000, approved by the State Council, the administrative office of Yuncheng was withdrawn, and the Yuncheng prefecture-level city was set up, which is subordinate to the city of Yuncheng. The city is situated on National Highway 209 running north-south, National Highway 108 running east-west, Houma (West) Railway and Houyu Expressway running through the whole city. In November 2021, Hejin was selected as one of the "Four Good Rural Roads" National Demonstration Counties, and in May 2022, it was honored as a National Sports Industry Demonstration Base.
In 2022, Hejin realized a GDP of 42.35 billion yuan, an increase of 7.1% over the previous year at comparable prices.